#separator:Tab
#html:false
#tags column:5
IMF-085-01-0001-en	Why is clinical gestational age usually about two weeks greater than developmental age?	Developmental age is counted from fertilisation, whereas gestational age is counted from the first day of the last menstrual period, which precedes fertilisation.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0002-en	Primordial germ cells are specified outside the future gonad. Why does this create a route to infertility or germ-cell tumours?	They must migrate to the genital ridges and depend on somatic signals to survive and differentiate, so failed migration, survival or differentiation can cause infertility, gonadal dysgenesis or germ-cell tumours.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0003-en	In spermatogenesis, what distinguishes the separation in meiosis one from that in meiosis two?	Meiosis one pairs, recombines and segregates homologous chromosomes to form haploid secondary spermatocytes; meiosis two separates sister chromatids to form round spermatids.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0004-en	How does a round spermatid become a spermatozoon without further division?	Spermiogenesis remodels it: the nucleus condenses, Golgi-derived vesicles form the acrosome, a flagellum develops with mitochondria around its proximal segment, and excess cytoplasm is discarded.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0005-en	Why can sperm just released into the seminiferous tubule lumen not yet fertilise an oocyte?	They are not yet fully motile or fertilisation competent; they mature during epididymal transit and are later mixed with accessory-gland secretions at ejaculation.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0006-en	How is development coordinated across spermatogenic cells, and which two hormonal actions does the process require?	Cell generations stay linked by cytoplasmic bridges that coordinate development, and the process requires testosterone from Leydig cells plus follicle-stimulating-hormone action on Sertoli cells.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0007-en	Why is the female follicular pool finite, unlike the male germ-cell supply?	Oogonia proliferate during fetal life, then arrest as primary oocytes in prophase one within primordial follicles; the pool then declines through atresia and ovulation, whereas basal spermatogonia maintain a stem-cell population.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0008-en	What is the purpose of the unequal cytokinesis that produces polar bodies during oogenesis?	It preserves cytoplasm and organelles in one large cell, first the secondary oocyte and then the mature ovum, leaving the first and second polar bodies small.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0009-en	Why does aneuploidy risk rise with maternal age?	Oocytes remain arrested in meiosis for years, and over that time cohesion and spindle errors increase.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0010-en	How do theca and granulosa cells divide the work of follicular oestrogen synthesis?	Theca cells make androgen precursors under luteinising hormone, and granulosa cells aromatise those precursors under follicle-stimulating hormone.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0011-en	Why is capacitation described as a sequence rather than a single switch?	It is a series of biochemical changes in the female tract, influenced by bicarbonate, calcium, albumin and tract signals, that alter surface components, membrane properties and motility to prepare for the acrosome reaction.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0012-en	What does sperm-oocyte membrane fusion set off in the oocyte?	Calcium oscillations that drive completion of meiosis two, metabolic activation, and mechanisms that prevent polyspermy.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0013-en	How does the cortical reaction prevent polyspermy, and why must polyspermy be prevented?	Granule contents released beneath the oocyte membrane modify the zona pellucida so further sperm cannot productively enter; extra sperm genomes would disrupt chromosome balance and spindle organisation.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0014-en	How do the maternal and paternal genomes come together after fertilisation, given that intact nuclei do not conventionally fuse?	Each pronucleus forms, replicates its DNA and approaches the other, and their chromosomes align together on the first mitotic spindle.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0015-en	Why does successful fertilisation not guarantee a clinically recognised pregnancy?	Many conceptions fail before clinical recognition because of chromosome or developmental abnormalities, even though fertilisation restored diploidy and started cleavage.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0016-en	How do compaction and cell position lead to the two lineages of the blastocyst, and what does each form?	Compaction at about the eight-cell stage creates inner versus outer differences, so polarity and position bias cells: outer trophectoderm forms mainly placenta and extraembryonic tissue, inner cell mass forms the embryo proper.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0017-en	How does the zona pellucida both protect normal implantation and relate to ectopic pregnancy?	It prevents premature adhesion during tubal transport and must be shed by hatching before contact with endometrium; if transport is delayed or the tube is impaired, implantation can occur outside the uterus, most often in the tube.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0018-en	What changes make the endometrium receptive to the blastocyst?	During a limited progesterone-dependent window in the secretory phase, stromal cells decidualise, enlarging, storing glycogen and lipid, and changing immune and vascular signalling.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0019-en	What distinguishes the roles of syncytiotrophoblast and cytotrophoblast during implantation?	Multinucleated syncytiotrophoblast invades epithelium and stroma without cell boundaries, eroding maternal capillaries and glands; mononuclear cytotrophoblast remains the proliferative source of new trophoblast.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0020-en	Why is human chorionic gonadotropin essential in early pregnancy, and why are its trends more useful than one value?	It rescues the corpus luteum to maintain progesterone until the placenta makes enough steroid; its level varies widely, so trends with ultrasound context are more informative than a single value.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0021-en	Why must trophoblast invasion be controlled rather than maximal?	Insufficient remodelling of maternal vessels contributes to placental insufficiency and hypertensive disorders, whereas excessive invasion can penetrate abnormally deep into the uterine wall.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0022-en	What distinguishes the fates of epiblast and hypoblast in the bilaminar disc?	Columnar epiblast next to the amniotic cavity generates all three embryonic germ layers, whereas cuboidal hypoblast contributes to yolk-sac lining rather than the embryo proper.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0023-en	How does formation of the chorionic cavity split extraembryonic mesoderm, and what keeps the embryo attached?	Coalescing cavities separate somatic mesoderm lining trophoblast and amnion from splanchnic mesoderm covering yolk sac; the connecting stalk links embryo to chorionic wall and later contributes to the umbilical cord.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending
IMF-085-01-0024-en	Why does preimplantation genetic testing not guarantee implantation or a healthy child?	It samples trophectoderm cells and yields only selected genetic information, while culture conditions, embryo selection, transfer number, parental age and underlying infertility also shape outcome.	Integrated Medical Foundations; chapter 85, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 1635d42967dc6a2ab9c4390195a5a186dfb275dbca8ae2ec5feb96c714528229; editorial review pending	imf lang::en chapter::085 module::085-01 review::pending